Electric lamp.



J. o. CAMP, Jn.

ELECTRIC LAMP APPLICATION FILED JULY 28,1910.

Jan.

Patented l, Inventor Attorney y JAMES oscAR CAMP, .Timor JACKSONVILLE, ALABAMA.

vTo all 'whom/t may concern:

ELECTRIC LAMP.

Specification of Letters Patent.

Application sied .nay 2c, 1910'. serial No. 573,921.

Be itvknown that'l, JAMES O. CAMP, J r., a citizen of. the,` United States, residing at' Jacksonville, in the county of Calhoun and State of Alabama, have invented a newand .usefulElectric Lamp, of which the following `isa specification..

Thiu `inuent'on has yreference to yimprovementsiiiflectric lamps, more .particularly to electriclampsofgthe incandescent type and its objectyistoprovidea lamp which may be manipulated afterfthe manner of an ordious-intensitiesatthe will of the opera# tor,thebulb.of the-1am containin a numv Y naij'yjwick lamp to give light outputs of var V- 15 b'er 'off filaments of di erent cand e power capacity, beginning with a low candle power and .being capable of being coupled into the circuitprogressively' so that the increasing candle power of the lam is due to the addition of filaments of individually lower canc dle ower-.tlian the total out-put of the-lamp.

T elinvention will` be best` understood from4 aconsideration of the following detailed description. taken in connection with the accompanying drawings forming ya part lof lthis specification, in which drawings,-

. Figure 1 isa diametrical longitudinal section oan incandescent electric'lamp constructed in accordance withthe present invention. Fig. 2 is a .similar section at right angles to that of Fig, 1. Fig. 3' is a detail section through the central circuit means.`

' Fig. 4 is a detail "section through a portion 'of the shell of the lampfba'se showingcon- 4vtact terminals.4 v lRei'erring" to the drawings there is shown an incandescent electric lamp bulb 1 which may be taken as indicative of any Suitable type of incandescent lamp since the. invention is not necessarily confined to the lparticular-type shown.

, In the example` illustrated in thev draw-Y ings there are four separate filaments 2, 3, 4',

5, respectively all su ported in the usual pillar 6 at the base endpof'the bulb where these ilaments are sealed in the usual manner. One sideof each of the laments has'a common connection" to' a terminal filament or conductor 7. i j

The base end of the lamp iscarried by a cylindrical shell .8 in which the lamp may be secured by the usual plaster-of-pa'ris filling .9 `or lin any yother suitable manner.v This shell 8 carries at spaced intervals on one sidel circuit terminals 10 each of which is connccted to av respective filament 2, 3, 4, 5.

.The shell 8 has a central inset tubular por-` tion' 11 which in the particular' structure shown is provided with aninsulating lining 12 carrying at tlic ilinerfend of the tube 11 a conducting'block 13 ltowh-ich is attached by 4soldering -or` otherwise the common conductor 7. The terminals ofthe filaments 2', 3, 4 and l5 remote from the common terminal 7 are carried through the member 6 and ultimately to the several contacts 10 which are' Patented Jan. 24, 1911.

carried by the c lnder 8 but insulated theizefrom by suitab e insulating material 14 as best shown in Fig. 4. Along one side of the cylinder 8vis a rack 15 for a purpose which' will presently appear.

The lamp is provided with the usual screwbase 16 shaped however to receive thefcylindrical basic portion 8 of the lamp in a manner which permits the portion Y8 to slide axially in thelbase 16, the latter being provided with exterior screw threads 17 adapting the base`16 to. the usual lain socket. The base 16' has the central termina 18 common to ordinary 'Edison lamp bases and this terminal isformed on one end of a post 19 i 'i axial to the base and extending into 'the insulation .within they tubular sleeve 11. Housed between the' end of the post l19 where entering thetubular sleeve 11 and the contact 13 isa spring 2O serving as a conductor for coupling the terminal 18 to the .tact irrespective of the position of the lamp base8 in the supplemental screw base 16. Along one side of thesuppleinental base 16 a contact terminal 21 adapted to engage any one or all ot' the contacts 1t), or these' contacts may engage the inner .vall of the supplemental base 16,(lirectly, the purpose being simply to establish contact between the supplemental base 16 andthe terminals 10 in a manner tobeI hereinaftcr'described. One side of the supplemental base 16 beyond the screw thread 17 is formed with an off-set 22 housing a piniony 23 on an arbor 24'terminating in the usual manipulating wheel 25 such as is commonly found in lamp burners. l

The set screw 26 carried by an appropriate. portion of thesu plemental'base 16 'and ex' tending into a sot 27 in a corresponding portion of .the basic part 8 of the lamp permits axial relativemovement of the sup le mental base 16 and the basicportion 8 ast to the lamp bulb withinthe limits of the terminal `13 and maintaining electric conlength of 'the slot but prevents accidental separation of the parts.

The supplemental base l16 though shown as oft-he Edison type may ofcourse be of any other of the known types of lampbases y and the base `16 is adapted to the usual socket in the usualway so that'the terminals of the socket make eontactwith thebody of the base 16 and the central insulated terminal 18.

The arbor 24 may be turned in a 'manner to carry the base portion 8 of the lamp outwardly with relation to the supplemental base it untilvall the terminals 10 are outside of and out of Contact with the terminal member 21. Under these circumstances none of the filaments is in circuit with the power -line coupled to the` lamp socket and consequently none "of the filaments will glow. Suppbse-now that it is desirable to have the lamp give forth a comparatively" feeble light. AUnderthe'se circumstances the arbor 24'is turned in a direction'to cause the lamp4 base'S to move into the supplemental base 16 4'until the first one of the contactsV 10 is brought into engagement with the; Contact 21 when there is established a circuit from the supplemental base 16 to the rst'of the contacts 10, thencethrough a filament 2 and 'by way oit the filament terminal to the terl minal 13 and by the spring 2O tothe termin'al post 19 and ultimately to the terminal 18 rin contact withpthe -like terminal in the lamp socket. Now current 'will'fiow to-:the filament 2 and a light such as this 'filament is designed to give will beproduced by said ,filament.` Ordinarily this filamentvvill be designed. to give a light Aof say two candle vso power.A vBy `further turning the arbor 24 the second one ofthe contacts is brought l into engagement with thek contact 21 and the filament' 3 will glow. Assuming this fila-- ment^to give-a candle powerfof six then theI lamA will produce a light equal to eight can les since the filaments 2 and 3 are under these circumstances both energized.- `Eurther Amovement or' the ylamp base 8 into the supplemental basel() brings the filaments-4 and 5 in order into circuit, the filament 4, being,

say, of eight candle power so that the. com-A bined candle power of the three filaments is sixteen candles. The filament 5 may be of sixteen candle power so that the entire output of the lamp in'lightV isr thirty two'candles. lVithl the` particular arrangement.-

shown the lam will giveout light in the order of two, eight, sixteen and thirty two candles at the will of' the operator. It so i of telescopin great a variety of degrees of light is not desired less filaments Amay be used and if a greater variety 1s desiredv more vfilaments may be used and, ,if wanted, a greater candle power provided. l l

By-means of the arbor 24 and the telescoping arrangement of the lamp baseinto .the

supplemental exterior base the manipula tion otthe lamp is very similar to the manipulation of an ordinary kerosene lamp vwhereby the lightis made bright or .dim by turning up or down a wick. NV ith `the present nivei'ition thelight 1s turned up, or turned down through several steps like an ordi-nary kerosene lamp. Should onev -Iilanie1it or more than one filament break the lamp is still in useful'condition sincel the filaments are in multiple when in servicev and all thev benefits of intense or dim light are retained with consequent. economy inv the use of current. What isv claimed is l. An incandescent electric lamp provided with a plurality of lfilaments of different y candle powers, a,base for -the lamp 'having separate. circuit 4terminals for one end ot each filament and a common terminal for the other ends of the filaments, a supplemental base in surrounding relation to the first named base and in which the first` named base is capable of telescoping, -said supplemental base having its exterior corresponding to a standard base and adapted to c a standard lamp socket, and means for causing a 'relative axial movement of one base withv respect to the other.

2. An incandescent electric lamp provided 'with a plurality of filaments of" diderent candle powers, a base for the lamp having separate circuit vterminals for one end of each filament and common terminal for the other ends ott-he filaments,A another base intowhich the first named base is capable movement,v the second' base being adapte to a lamp socket, and a rack .and pinion'actuating mechanism for impart ing relative movement between the two vbases in the 'direction of the' longitudinal 

